Process of treating potassium-bearing minerals.



eunnnc, census.

BARKER? MINERALS.

music-crumb l, process sis, and

potasto obtain. urn having r, re son s essecie lements of zinc silicate,

oi" Charters Eeteniz,

Patented Aug. 3, 1915.,

Serial No 28,589.

.irom rces passing from the furnace by method, such, for example, as condor mg c116 fumes escaping from the kil or fu ice, preferably by means of a his stack-Washer, and extracting the salts in form of potassium id, with Water from the condensed During the first step of the process, ochloric acid gas is formed in large may be recovered in the form of hydrochloric acid, ihus er'iecting a material economy in the practice of the invention. 4

The sulfuric acid acting on the sodium chlorid produces hydrochloric acid gas, and the combined ecion of the nascent hydrochloric acid the concentrated suli do acid of the oath upon the silicate purcicles serves to initially break up the combination, and produce soluble potassium compounds, Moreover, the further resultant action of the sulfuric acid and nascent hydrochloric acid gas of the bath is to convert the silicate particles into such condition that they are more readily acted upon by the roasting of the second step of the process, thus converting a still further portion of the potassium of the silicate into soluble-potassiuni compounds. By these means, approximately all of the potassium ofvthe silicate may be recovered in the forms of potas sium sulfate and potassium chlorid.

is a specific example of my process, I

oc 5 follows: Take 100 parts of powcate; parts of sodiumchlorid; 3 IuSW'fi? carbon; and 50 parts of conrated sulfuric acidall by Weight. The potessiumbearing silicate, such, for exames feldspar, is ground to pass through mesh This powdered silicate is tinzately mixed With'the alkali chlous sdium chlorid, in a granular -r with the reducing substance, crude carbon in a finely pulverized tion. This intimate mixture is then troduced into the bath of concentrated l acid, preferably from to aum strength. The whole mess is then jected to a temperature of about 200 3., until the reactions are complete. Durthis step of the process, the resultant hydrochloric acid gases are preferably conducted 0% and recovered in the form of hydrochloric acid. After the reactions in the oath are complete, and the resulting roduct has been ellowedto cool, it is pu venzed and placed in a suitable furnace, where it is roasted in the presence of air, the. temperature being raisedv to approximately '1000 to 1150 0., until tests show that the silicates are decomposed. The duration of the Q treatment of the mixed materials is about two hours, and the heating should be con} or cinder containing water-soluble potassium salts, together "with' sodium sulfates that have been formed in" the reaction. This clinker or cinder, may begground and subjected to the action of water, preferably heated, for dissdlving out the-salts, after which the potash salts may be recovered by any suitable method.

By means of the process above described, I am enabled to recover on a"commercial scale a larger amount of potash than has heretofore been found practicable. The proportions of sodium chlorid and sulfuric acid to, the powdered silicate above specified are given byway of example, but it will be understood by those skilled in the art that theymay be .varied depending on the refracto characterof the potash-bear in 'rock sub ected' to their action.

at is claimed is f 1. The process of rendering potassium salts in silicates water-soluble which consists in subjecting the silicate in powdered form together with sodium chlorid to the action of a bath of concentrated sulfuric ac d in the presence of heat.

2. The process of treating potassiumbearing silicates which consists in subject'- ingthe silicate in powdered form together with sodium 'chlorid .and pulverized carbon to'the action of a bath of concentrated sulfuric acid'in the presence of heat, then pulverizing the resulting product and roasting the same at a temperature of from 1OO0 to 1150 C. p

3. The process of "treating potassium- I bearing. silicates to recover potassium salts therefrom which consists in intimately mix- .ing powdered silicate, pulverized carbon,

and sodium chlorid', then introducing the.

v mixture into. a bath of concentrated sulfuric acid, then heating the'whole, pulverizing the resulting product, and then roasting the same at'from 1000 to 1150 C.

4, ,The process of treating refractory potassium-containing compounds for obtaining soluble potassium salts therefrom con-.

sisting in subjecting ysaid compounds incommmuted condition together with sodium chlorid and comminuted carbon to a bath of remove the soluble salts. 1 a,

e The process of treatingv potassium containing feldspar -for'obtaining soluble po- I scribing witnesses.

concentrated sulfuric acid partially-decompose said refractory compounds, and

roasting the resulting product-in presence of air.-

5, The process of treating refractory pochloridand comminuted" carbon to a bath of concentrated sulfuric acid while heating the same to about 200 C. to partially decompose said refractory compounds, and roastmg the resulting product in presence of air.

6. The process of treating refractory vpotassium-contamingcompounds for obtaining soluble 'potassiumsalts therefrom con;

' in subjecting said compounds in sistm commmuted condition to concentrated sulfuric acid in presence ofnascent hydrochloric acid gas and heat of about 200 C.

7. The processjof treating refractory po tassium-containing compounds for' obtaining soluble otassium' salts therefrom consistingin su jecting'said compounds with carbon in comminuted condition to a bath of concentrated sulfuric acid in presence of nascent hydrochloricacid gas'and heat of about 200 and then roasting the resulting product in 8. The process 0 presence of air,

taining feldspar for obtaining soluble"potassium salts therefrom consisting inintroducing the comminuted feldspartogether withjsalt and comminuted carbon intoa bath of concentrated sulfuric acid, heating the mass, then roasting the resulting pro-' treating potassium conduct in presence of air at a temperature of from 1000 to 1150 C., and extracting the comminuted roasted product with water to 'tassium salts therefrom consisting in subjecting the comminuted feldspar together with salt and comminuted carbon to a bath of sulfuric acid, heating the mass, then roasting the resulting product in presence ofair at a temperature from 1000 to 1150?- a C, and recovering the potassium salts with water from the oration. v

In testimony whereof I-have signed this specification-in the presence of two sub SAUL E. MELKMAI I.

Witnesses: S. T. (Lemon,- W. B. Knmuu.

products ofthe roasting op 

